—Dad, I've finished my assignment.—Good，and ________you play or watch TV, you mustn't disturb me.

Now there is just one point   I wish you to make clear.

 Beijing is ranked first in terms of traffic jams and expenses for culture ________ Guangzhou is more open to peasant workers than Beijing and Shanghai.

—Where’s that report?—I brought it to you _______ you were in Mr.Black’s office yesterday.

________ excited Geoff Marcy most was whether there were planets in other solar system where life might exist.